I played the SW in my set of G15 and loved it. I've since moved towards a more traditional wedge, but wouldn't have a problem with the G series wedge. What do you tend to use the SW for?
Completely dependent on what you are using it for. The Glide will offer a bit more versatility and the G Series set wedge will have more forgiveness and obviously natural gapping for use when primarily full swings are in play.
And of course if you opt for more versatility, a golfer can choose any brand as their wedges do not need to match.
The glide will definitely let you be more versatile, but its all about what you like/want to do with that club. Imo the glide wedges were some of the best out there this past year.